Compressor for air and gases



2 'Sheets-Sheet 1.

(No Model.)

T. O. ORAVEN.

COMPRESSOR FOR AIR AND GASES.

No. 451,460. Patented'MaJy 5, 1891.

(No Model.) 2 Sheets-Sheet 2. T. C. CRAVEN. COMPRESSOR FOR AIR ANDGASES.

YME Numus Ps1-Ens co., muraurno, wAsNxNnmN, uA ci NITED STATES PATENTnOFFICE.

THOMAS C. CRAVEN,OF NEWARK, NET JERSEY.

COMPRESSOR FOR AIR AND GASES.

SPECIFICATION forming part of Letters Patent No. 451,460, dated May 5,1891,

Application iiled June 7, 1890. Serial No. 354,544. (No model.)

To all whom it may concern 13e it known that l, THOMAS C. CRAvEN, 'acitizen of the United States, residing at Newark, in the coniity ofEssex and State of New Jersey, have invented an Improvement inCompressors for Air and Gases, of which the following is aspecification.l

.Great'difficulty has heretofore been experienced in pumping air andother gases when undei` a very high pressure, because the expansion ofthe air either in the cylinders or the passage-ways frequently prevents:the drawing in of a fresh supply upon the backstroke, and thecompression of the air in the cylinder at the end of the stroke is oftenbut little more than the pressure of airin the reservoir into which suchairis forced.

In my present invention I make use'of a pump that acts upon the water orsimilar iiiud, and this water is automatically directed into one or twocylinders or chambers and displaces the air therein, forcing the sameout from the vessel and into a receivingchamber after the pressure hasaccumulated sufliciently to pass by the retaining-valves, and when onecylinder is full of liquid the connections are automatically changed tothe other cylinder and the operations are repeated therein, While thewater is allowed to run out of the first cylinder and atmospheric air topass in and take its place, so that this cylinder is ready for the airto be compressed therein, when the automatic mechanism is again shiftedfrom one cylinder to the other.

In the drawings, Figure 1 is a plan view at the line c of Fig. 3. Fig. 2is avertical section at the line y y, Fig. 1; and Fig. 3 is a verticalsection at the line ze of Fig. 2, showing also the upper portions of theair-cylinders and valves in section. Fig. A is an elevation of one ofthe float-valves.

The air-cylinders A B rest upon andare bolted to the base-plate C, andbelow this base-plate or within the saine is the valvechest D with acover 2, and within the valvechest is the frame E around the valve F,and there are ports 3 and et in the valve-seat leading to the respectivecylinders A and B, andv there is an exhaust-port 5 leading to thedischarge-pipe G. The valve F is represented as an ordinary Dslide-valve, as the same is best adapted to this apparatus; but I do notlimit myself in this particular.

The water-supply pipe H leads from any suitable water-pumping apparatusto the valve-chest D, and by the valve F water is directed through theport 3 to the cylinder A or through the port a to the cylinder I3,accordin g to the position of the valve.

At the top ends of the respective cylinders A and B are valves I withinthe conical heads K of the respective cylinders, and at the apex of eachconical head is a check-valve G at the junction of such conical head Kwith the branch pipes Ii, leading to any suitable airholding vessel oraccumulator. It is preferable to place an adjusting-screw 7 over each ofthe check-valves 3 to limit the movement of such valve, the said adjusting-screw passing throughperforated bridge pieces or disks, and Iremark that it is preferable to have upon each valve 6 a cylindricalstein S to the valve, the same sliding within the cylindrical or tubularportion at the apex of the conical head, and this cylindrical portion ischanneled upon its edges up to the valve, the channel being sufficientlylarge for the free passage of the air under pressure as it is forcedfrom the cylinder A or the cylinderB into the branch pipe L.

Each of the valves I is conical in its external configuration, and thestein 9 passes through and is guided by the bridge or perforated disk10, so that the valve when open rests upon such bridge 10, and in orderto close the valve a float 11 is provided for each valve, which isusually conical and held between strips or basket-shaped supports 13from the valve I, and I prefer to make the iioat 1l of cork.

Upon the Valve-frame E and at opposite ends thereto are the rods 13 andle, passing through stuffing-boxes 15 at the ends of the valve-chest D,and at each end of the valvechest and lin line with the same arecylinders M N, containing valve-moving pistons O and P, that arepreferably provided with cupleatliers and permanently connected to therespective rods 13 and 14, and there are pendulous levers Q, pivoted at1G and provided with weights R, and these pendulous levers are connectedby link-joints 17 and 1S to the valve-moving pistons t) aud l),respectively, and iii line with the rods l-i aud Al-l-,and there is ahole ft.) passing from the cylinder A into the cylinder )l and a similarhole 2O from the cylinder B into the cylinder N,and these cylinders Mand N remain full of water between the valve-moving pistons O l and theends of the valve-chest D. The valve-chest D also remains full of water,and the operations of the parts are as follows:

lVater being forced through the supplypipc ll by competent power appliedto a pump, such water is admitted bythe valve F to one of the ports 3 ori-. In Fig. l. the

water is represented as passing by the port 23 into the cylinder A, andas the water rises in such cylinder the air above it is compressed, andwhen the pressure of the air becomes equal to the pressure of the air inthe branch pipes L the valve G opens and the air under pressurecontinues to pass into such branch pipes L andthe container oraccumulator, and when the water rises around the float ll the waterlifts such float and closes the valve l, so that water does not passinto the pipes L, and the water in the cylinder A being now confined thepressure accumulates and the water passes through the hole lf) into thecylinder M, and the pressure becomes sufficient against the valve-movingpiston O to move the same along in the cylinder M against the action ofthe pendulous levers Q and weights R, and the frame E is moved at thesaine time, and the weights pass over the pivots of the pendulous leversshortlybefore the end ofthe frame E comes in contact with the valve, andas the pendulous leversQ and weights fall in the other direction thevalve F is moved and the water admitted to thecylinderB throughtheportt. Duringtheforegoingoperationthe water in the cylinder B hasbeen running out by gravity because the valve F has opened a passage-waybetween the port l and the exhaust-port 5, and during this operation thevalve G tothe cylinder l has been closed; but airis admitted into suchcylinder B as t-lie water runs out in consequence of the cheek-valve S,of any suitable construction, opening inwardly and connected with thecylinder B or its conical head l, and the supply is such as to allow thecylinder l5 to become emptied, or nearly so, by the time the cylinder Ahas become filled and the valve changed, as before mentioned, and afterthe valve has been changed the water under pressure passes by the port iinto the cylinder l, the cheekvalve S closes, and as the wateraccumulates and the pressure increases the valve G to the cylinder B isopened and tlieair under pressure passes to the branch pipes L andaccuniulator until the valve I of the cylinder ll is floated and closes,and the water under the accumulation of pressure passes by the hole 20into the cylinder N and gives motion to the valve-moving pistons andvalve in the same manner and in the opposite direction before set forth,and during this operation thc water has been ruiming out from thccylinder A through the port 3 alid ixliaust-port 5, the air enteringsuch cylinder A through the cheek-valve T, and it willbe apparent bythese alternating` operations the air is compressed in first onecylinder and then in the other by the direct action of the water, andthe water-pump can be run at any desired speed and the cylinders A andll can be of any desired size. llenee the pressure of air can be veryhigh, according to the uses to which the compressed air is put, andthecylinders A and I3 become air-puinping cylinders with water-pistons, andsuch cylinders do not become highly heated by the compression of theatmosphere, because of the cooling action of the water, and such wateras it is run out from first one cylinder and then the other may bereceived into a vessel sufficiently charged to allow such water to coolbefore it is used over again.

In cases where a pump is used to compress air to the extent of two orthree atmospheres it can be made to operate reasonably well, and henceair under such pressure may be supplied by pipes through thecheck-valves S T into the cylinders A B, and the powerful compressionwill be effected by the water in such cylinders A B as it rises, asaforesaid.

It will be apparent that the weights R can be adjusted to any desiredposition, and the 'farther the weights are elevated the higher thepressure will have to accumulate before the valves are moved and thegreater will be the leverage exerted by such weights in moving thevalves, and by adjusting these weights the amount of pressure thataccumulates in the cylinders before the valve F is moved will bedetermined.

It is to be understood that water always remains in the cylinders M Nbetween their stationary heads and stuffing-boxes l5 and the respectivepistons O P, and that the passage-ways lt) and 2O are full of water andalways reinain open into the respective cylinders; but the weights R,acting on the levers, valve-rod, and valve-moving pistons, prevent thepressure of water moving the valves until the pressure in one of thecylinders A oi' B is sufficient to overcome the resistance afforded bythe said weights R and levers Q, and this pressure varios according tothe position of the weights on the levers and the leverage exerted bythem to hold the valvemoving pistons in a state of rest. XVhen thepressure becomes sufficiently great in one cylinder A or l, (the othercylinder at that time is being diseharged,) the water that is forcedinto such cylinder passes through the port 19 (or 20) and moves thepistons 0 alid l) from one position to the other7 and the valve F ismoved as soon as the levers Q pass the vertical position and are actedupon by the weights to cause them to swing downward and give motion tothe valve-rods 13 14E to cause the water-supply to pass to the othercylinder and open the discharge of tlietirst cylinder. rllic ITOpositions of the weights R can be adj usted so that their leverage willbe more or less, and a greater or less pressure will have to accumu-vlate before motion is given to the valve. Hence a safety-valve to theapparatus is not needed, as the cylinders A B will dischargesuccessively and automatically, and should the pressure in the pipes Lbe greater than that at which the weighted levers Q R are set to mowe noair will be forced into such pipes L; but so soon as the pressure in thepipesL is lessened the air will be forced in by the successive rising ofthe water in the vessels A B. The floats l1, being immediately below thevalves I, act directly upon them, and when the water accumulateslsufficiently to lift the float the valve is closed, and thereby theflow of water from the vessel A or B into the pipe L is prevented, andbeing confined the water as it is pumped into the vessel causes an in.-crease of pressure and the Water goes by the passage 19 or 2O into thecylinder M or N and acts directly upon the valve-moving piston O or Pand the weighted levers to change the position ot' the valve and directthe lWater into the other cylinder.

I claim as my invention- The combination, with a pipe through whiclwater' under pressure is supplied, of a valve and valve-chest .receivingthe water, vertical waterreceiving cylinders or vessels, ports leadingfrom the valve-seat to the receivingcylinders and to an exhaust,air-valves and floats at the upper ends of the water-cylinders, andpipes to convey away the compressed air to a receiver or holder, andvalve-moving pistons and cylinders for the same, provided withuncontrolled openings between the respective water-cylinders andcylinders for the valve-moving pistons, whereby the valve is' moved toadmit water to one cylinder or the other automatically, substantially asset forth. Signed by me this 4th day of June, 1890.

THOS. C. CRAVEN. Witnesses:

Gno. T. PINCKNEY, WILLIAM G. MoTT.

